1. Field of the Invention
The present invention relates to a computer system and a control method therefor, and more particularly, to a computer system, such as a portable computer, and a control method which can receive a video signal from an input source such as an external computer and provide a visual display of an image based on the video signal.
2. Related Art
Generally, a computer system supports various communication ports to communicate with an external device. Such a computer system is generally a portable computer, such as a desktop, laptop, notebook or palmtop computer, a personal digital assistant (PDA) and a mobile device. For example, the portable computer supports a monitor output port arranged to connect with an external display device, and outputs a video signal to the external display device, via the monitor output port. As a result, the external display device can provide a visual display of an image that is the same image displayed at an internal display panel provided to the portable computer. Examples of such a monitor output port include a D-sub port for outputting an analog video signal, and a DVI (digital visual/video interface) port for outputting a digital video signal.
However, when the portable computer does not output a video signal to the external display device, but rather receives a video signal from an external input source, such as an external computer, a separate video input port, such as a separate jack, must be provided.
In other words, a separate jack is needed for installation in the portable computer so as to receive a video signal from an external input source between the internal display panel and an internal graphic processor. In addition, a video multiplexer is also needed for installation in the portable computer so as to selectively output either a video signal received from an external input source or an internal video signal to the internal display panel.
However, if the separate video input port and the multiplexer are additionally mounted or installed in the portable computer, the simplicity and the portability of such a portable computer can be compromised and deteriorated. Moreover, the configuration of such a portable computer may get complicated.